Supporting structure for steelmaking converter vessels



Dec. 19, 1967 ss ETAL 3,358,984

SUPPORTING STRUCTURE FOR STEELMAKING CONVERTER VE SSELS 4 Sheets-Sheet 1 Filed Feb. 5, 1964 FIG.

FIG. 2

Dec. '19, 1967 H. GRASSIN ET SUPPORTING STRUCTURE FOR STEELMAKING CONVERTER VESSELS v 4 Sheets-Sheet 2 Filed Feb. 5, 1964 Dec. 19, 1967 H. GRASSEN ETA!- 3,353,934

SUPPORTING STRUCTURE FOR STEELMAKING CONVERTER VESSELS Filed Feb. 5, 1964 4 Sheets-Sheet 3 Dec. 19, 1967 GRASSlN ET AL 3,358,984

SUPPORTING STRUCTURE FOR STEEITMAKING CONVERTER VESSELS Filed Feb. 5, 1964 4 Sheets-Sheet 4 v United States Patent 3,358,984 SUPPORTING STRUCT FOR STEELMAKING (ZQNVERTER VESSELS Henri Grassin, St. Etienne, and Pierre Meynard, St. Charnond, France, assignors to Compagnie des Ateliers et Forges de la Loire (St. Charnond, Firminy, St. Etienne, Jacob-Holtzer), Paris, France Filed Feb. 5, 1964, Ser. No. 342,637 Claims priority, application France, Feb. 15, 1963, 925,059, Patent 1,378,826 3 Claims. (Cl. 266-36) This invention relates to converters as used in the Bessemer steelmaking processes and the like and is more especially concerned with the structure serving to support the converter vessel.

The vessel of a converter must be supported for pivotal rotation about a horizontal axis to move the converter to its different operative positions as required during charging, blowing and pouring. Since the sheeting from which the converter vessel or shell is made is liable during the blow to be carried to relatively high temperatures which can well exceed 200 C., it is customary to support the vessel within an annular frame or ring member coaxially surrounding the vessel in radially spaced relation with it, and to provide the horizontal pivots or trunnions on such frame member. This avoids the danger of heating the trunnions excessively and also of causing trunnion misalignment due to thermal distortion as would inevitably occur at the temperature involved were the trunnions secured directly to the converter vessel. In such a converter construction, the means supporting the converter vessel within the annular frame member must include only a limited number of spaced areas of engagement so as to restrict heat transfer from the vessel to the frame member. At the same time such suporting means must be so designed and constructed as to ensure the requisite coincidence between the axes of revolution of the vessel and frame member while permitting relative thermal expansion between the two in radial directions, and also to locate the vessel and frame member axially with respect to each other while permitting relative expansion between them in the axial direction.

In conventional constructions these functions are achieved only imperfectly, as will be later explained in detail, and only at the cost of clearances which result in objectionable impacts of the converter vessel against the frame during the rocking movements of the converter. With present-day converter vessels of great size and weight frequently dimensioned to contain 200 tons of molten steel or more, such impacts become quite unacceptable.

A specific object of this invention lies in the provision of improved converter supporting structure of the type specified, wherein the functions of locating the vessel and frame radially with respect to each other (for coincidence of their axes) and of locating the vessel and frame axially with respect to each other are accomplished independently of one another and without mutual interference so as to permit full freedom of relative radial and axial expansion without objectionable clearance in any direction. A broader object is to provide improved converter supporting structure achieving smooth and efl'icient rocking movements of the converter at all operating temperatures and especially useful in connection with large-capacity converters.

Other objects will appear as the disclosure proceeds.

The invention in an important aspect comprises a converter structure including a converter vessel, an annular frame or ring coaxially surrounding the vessel in radially spaced relation therewith and pivotable about a horizontal axis and means for supporting the vessel from the "ice frame wherein said supporting means comprises first members on the vessel having a circumferentially spaced series of surfaces engageable with surface means of the frame along planes generally parallel to the common axis of the vessel and frame, and second members on the vessel separate and distinct from the first members and having surfaces engageable with surface means of the frame along planes substantially transverse to said common axis.

The invention will now be described for purposes of illustration but not of limitation with reference to the accompanying drawings wherein:

FIGS. 1 and 2 illustrate for explanatory purposes a typical converter structure according to the prior art, respectively in plan view and in section on an enlarged scale on the line lI- Il of FIG. 1;

FIG. 3 is a plan view of a converter structure according to an embodiment of the invention;

FIG. 4 is a section on line IVIV of FIG. 3; and

FIG. 5 is a section on line VV of FIG. 4.

In the conventional structure shown in FIGS. 1-2, there is provided a converter vessel 0 having a cylindrical intermediate section, which is surrounded by an annular frame or ring 1. The ring 1 is formed with diametrically aligned bosses 10 provided with axially aligned bore-s, as shown in FIG. 2, for receiving suitable trunnion means not shown to suspend the structure for bodily pivotal movement from an external frame about a horizontal axis. The means interconnecting the converter vessel or body 0 with the ring 1 comprise two circumferential series of brackets, a and b, suitably secured around axially-spaced circumferential areas of the converter body, as by being welded or bolted thereto. The brackets a and b have perpendicularly projecting flanges. The under surfaces of the projecting flanges of all the upper brackets a are adapted to engage the flat upper surface d of the ring 1, and the upper surface of the projecting flanges of the lower brackets b are similarly adapted to engage the fiat under surface e of ring 1 as will be apparent from FIG. 2. Such engagement serves to locate the vessel c and the ring 1 in their proper relative axial position. In addition, the flat surfaces d and e are formed with ribs such as f, provided with generally radial lateral surfaces, parallel to or extending through the axis of the ring 1, and engageable by complementary radial, lateral surfaces formed on the brackets a and b. This further engagement serves to locate the vessel c in centered relation within the ring, i.e., ensure coincidence between the respective axes of the vessel and ring, as is necessary especially during rocking operations. In the arrangement thus described, since both series of brackets a and b are directly secured to the sheeting of the converter vessel, by way of the vertical flanges of said brackets, it will be evident that the large temperature variations of the converter vessel sheeting will cause correspondingly large variations in the distance between the mutually facing surfaces of the projecting horizontal flanges of the brackets a and b, whereas the distance between the complementary surfaces d and e of the ring 1 will not be subjected to comparable variations owing to the considerably cooler condition of ring 1 as compared to the vessel 0. In the heated condition of the converter therefore, appreciable clearance will necessarily be present between the cooperating surfaces of the brackets a and b on the one hand and the upper and lower surfaces at and e of the ring 1 on the other. Such clearance, aggravated by other than thermal distortion effects in the sheet ing, have frequently resulted in objectionable impacts between the mating surfaces when the converter is rocked about its trunnions as for a pouring operation.

This serious defect is overcome by the invention in that the radial and axial locating and abutting functions are herein separated and assigned to separate and distinct structural elements. Referring specifically to FIGS. 3-5, there is again illustrated a converter structure including a vessel and an annular frame or ring 1. There are again provided two circumferential sets of brackets, 2 and 3, having their one flanges secured to the outer surface of vessel C as by bolting and welding at axially spaced circumferential areas of said vessel, and having their other flanges projecting horizontally from the converter. The brackets 2 and 3, in contradistinction with the somewhat similarly arranged brackets a and b of the conventional structure of FIGS. 1-3, herein cooperate exclusively to perform the radial locating or centering function, having lateral surfaces engaging complementary lateral surfaces of ribs or bosses 4,4 provided on the upper and lower surfaces and 6 respectively of frame 1. The mating lateral surfaces are suitably machined in the workshop or on site.

The brackets 2 and 3 are so positioned that in the cool condition of the converter vessel the spacing between the under surface of the horizontal flanges of the upper brackets 2 and the upper surfaces of the horizontal flanges of the lower brackets 3, is appreciably greater than the spacing between the upper and lower ring surfaces 4 and 4, whereby to provide a clearance space as indicated at 7. Thus the brackets 2 and 3 do not cooperate to ensure the relative axial location of the vessel 0 and ring 1, but only the relative radial locating or centering thereof as just explained above.

The axial locating function is herein accomplished by a third circumferential series of brackets 8 having their vertical flanges secured, as by bolting or welding, around the periphery of vessel 1: in such a position that the under surfaces of the horizontally projecting flanges of said brackets 8 rest on the upper surface of a lower horizontal wall element 6 of the ring 1. The said upper surface is flat and hence can be preliminarily rectified true in the workshop. The brackets 8 are preferably bolted or welded in advance to the converter vessel and their under surfaces may be rectified to a flat and coplanar condition either in the workshop or on site. The upper wall element 5 of the ring 1 is apertured as at 9 to enable the converter vessel 0 to be readily lowered into position within the ring 1.

It will be realized that with the construction described above with reference to FIGS. 3-5, the converter vessel 0 can freely expand axially with respect to the ring 1 without creating any clearance in the axial locating means, provided essentially by the upper surface of the lower ring flange or wall element 6 cooperating with the under surfaces of brackets 8. Since the distance, as measured axially along the shell of converter c, between the horizontal flanges of brackets 8 and 3 is very small, only a few centimeters in length, thermal expansions and contractions of the converter shell in the axial direction will not exert any substantial influence thereon.

It will be apparent that various changes and modifications may be introduced into the single exemplary embodiment shown and described without exceeding the scope of the invention.

What is claimed is:

1. A converter structure including a steelmaking converter vessel, an annular frame coaxially surrounding a cylindrical portion of the vessel in spaced relation therewith, means for pivoting the frame about a generally horizontal axis, means for Supporting said vessel from said frame, said supporting means comprising lateral surfaces on said frame, a first lower circumferential series of angle brackets having their one flanges secured around said converter vessel parallel with the vessel axis and having their other flanges arranged radially of said cylindrical portion of said vessel and formed with complementary lateral surfaces engaging said lateral surfaces formed on said frame, a lower wall element on said frame, a second lowef circurnferential series of angle brackets having their one flanges secured on the periphery of said vessel parallel with said vessel axis so that the under surfaces of the radially projecting other flanges of said second series of brackets rest on the upper surface of said lower wall element of said annular frame, the distance between said other flanges of said first lower series of brackets and said second series of brackets being of such a length that thermal expansions and contractions of said converter vessel in the axial direction will not exert any substantial influence thereon.

2. Converter structure according to claim 1 wherein said supporting means comprises moreover an upper circumferential set of angle brackets having their one flanges secured around said cylindrical portion of said converter vessel with a clearance space provided between their other radially projecting flanges and the upper surface of said annular frame.

3. Converter structure according to claim 2 wherein said upper surface of said annular frame is apertured to enable said converter vessel to be readily lowered into position within said frame.

References Cited UNITED STATES PATENTS 3,000,621 9/1961 Puxkandl 26636 X 3,146,983 9/1964 Johnson 266-39 X 3,163,696 12/1964 Johansson et al. 266-36 3,182,979 5/1965 Krause 26635 X 3,191,921 6/1965 Johnson 26636 3,191,922 6/1965 Puhringer 266-86 J. SPENCER, OVERHOLSER, Primary Examiner.

E. MAR, Assistant Examiner. 

1. A CONVERTER STRUCTURE INCLUDING A STEELMAKING CONVERTER VESSEL, AN ANNULAR FRAME COAXIALLY SURROUNDING A CYLINDRICAL PORTION OF THE VESSEL IN SPACED RELATION THEREWITH, MEANS FOR PIVOTING THE FRAME ABOUT A GENERALLY HORIZONTAL AXIS, MEANS FOR SUPPORTING SAID VESSEL FROM SAID FRAME, SAID SUPPORTING MEANS COMPRISING LATERAL SURFACES ON SAID FRAME, A FIRST LOWER CIRCUMFERENTIAL SERIES OF ANGLE BRACKETS HAVING THEIR ONE FLANGES SECURED AROUND SAID CONVERTER VESSEL PARALLEL WITH THE VESSEL AXIS AND HAVING THEIR OTHER FLANGES ARRANGED RADIALLY OF SAID CYLINDRICAL PORTION OF SAID VESSEL AND FORMED WITH COMPLEMENTARY LATERAL SURFACES ENGAGING SAID LATERAL SURFACES FORMED ON SAID FRAME, A LOWER WALL ELEMENT ON SAID FRAME, A SECOND LOWER CIRCUMFERENTIAL SERIES OF ANGLE BRACKETS HAVING THEIR ONE FLANGES SECURED ON THE PERIPHERY OF SAID VESSEL PARALLEL WITH SAID VESSEL AXIS SO THAT THE UNDER SURFACES OF THE RADIALLY PROJECTING OTHER FLANGES OF SAID SECOND SERIES OF BRACKETS REST ON THE UPPER SURFACE OF SAID LOWER WALL ELEMENT OF SAID ANNULAR FRAME, THE DISTANCE BETWEEN SAID OTHER FLANGES OF SAID FIRST LOWER SERIES OF BRACKETS AND SAID SECOND SERIES OF BRACKETS BEING OF SUCH A LENGTH THAT THERMAL EXPANSIONS AND CONTRACTIONS OF SAID CONVERTER VESSEL IN THE AXIAL DIRECTION WILL NOT EXERT ANY SUBSTANTIAL INFLUENCE THEREON. 